HP NonStop Pathway/iTS Programming Manual page 320

TCP Event Messages Event-Message Range 3000 Through 3999
Effect. The I/O operation fails.
Recovery. If a front-end process is being used, check that it is correctly coded to
emulate the type of the device specified. If a front-end process is not being used, see
Error Recovery on page 11-4 for instructions on how to locate the problem within the
program.
If this is not a program-related problem, run diagnostics for the device and make any
necessary repairs.
NonStop Pathway/iTS Management Programming Manual—426749-002
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